no
The answer will depend on what you wish to substitute in place of the inequality.
Good that can be used in place of another good.
You can substitute words which are synonyms. They can be used in place of each other.
A school.
A close substitute is a product or service you can purchase in place of another and still get the same satisfaction. There are many substitute goods available on the market.
in place of
Yes, the word 'substitute' is a noun, a singular, common, abstract noun; a word for someone or something that takes the place of another. The word 'substitute' is also a verb (substitute, substitutes, substituting, substituted). Examples:Noun: Salsa is a good substitute for tomatoes in a sandwich.Verb: Ms. Lincoln will substitute for Ms. Washington while she is on her honeymoon.
Really only trade would be a money substitute. That is it. But money substitutes are things that can be used in place of money.
Kiln
to substitute
You can use "in lieu of" as a substitute for "for."
Something used in a place of another thing is a substitute.